Electrochemistry of InSb as a Li Insertion Host: Problems and Prospects

Abstract

Ballmilling of In and Sb has been used to produce InSb for use in electrochemical and in situ X-ray diffraction studies ͑XRD͒ of Li/1 M LiPF 6 ethylene carbonate:diethyl carbonate/InSb cells. The cell capacity decays rapidly when cycled between 0 and 1.3 V, while the capacity reduction is less pronounced when cycling is restricted to the 0.65-1.4 V range. In situ XRD studies reveal that Li 3 Sb and In are formed during the first plateau ͑above 0.65 V͒, according to the reaction 3Li ϩ InSb → Li 3 Sb ϩ In. The indium product subsequently reacts with Li forming the InLi x phases InLi and In 4 Li 7 in sequence. When cells are cycled above 0.6 V ͑i.e., in the absence of InLi x formation͒ capacity retention improves significantly, remaining relatively constant near 250 mAh/g. Detailed in situ XRD studies of these cells suggest that 0.27 Li atoms per InSb may be intercalated during a sharp drop in the cell potential, according to the reaction xLi ϩ InSb Li x InSb (x max ϭ 0.27). This intercalation accounts for only a small ͑about 30 mAh/g͒ fraction of the overall capacity of 680 mAh/g. Consequently, it appears that the reactivity of In and Sb with Li, not the structure type, determines the reaction path. Therefore, InSb is not an attractive intercalation host for Li, in contrast to the claims made in the literature.In the search for negative electrode ͑anode͒ materials for use in lithium-based batteries, it has been recently proposed 1 that intermetallic compounds with the zinc blende structure may be attractive candidates. The suggestion is derived in part from the availability of interstitial Li insertion sites as readily seen along a ͓110͔ projection of the zinc blende structure. At room temperature and atmospheric pressure InSb crystallizes in the cubic zinc blende structure (F4 3m no. 216͒, and so in a recent paper 1 the electrochemical and structural characteristics of this prototype compound were tested to determine its effectiveness as a Li insertion host. It was reported that two Li atoms could be incorporated into InSb to form a hitherto unknown Li 2 InSb phase that displays very little ͑5.6%͒, volume expansion ͑relative to InSb͒. The new phase was claimed to form according to the reaction 2Li ϩ InSb → Li 2 InSb, while a subsequent reaction xLi ϩ Li 2 InSb → Li 2ϩx In 1Ϫx Sb ϩ xIn (x max ϭ 1) forms Li 3 Sb and In. The electrochemical cell exhibited good capacity retention ͑300 mAh/g͒ over 22 cycles. This prompted the authors to suggest that the results open up exciting possibilities for identifying other zinc blende insertion electrodes.Earlier work ͑not referenced by the authors of Ref. 1͒ on the reaction of lithium with InSb showed that only a small amount of Li could be intercalated within the InSb structure from solutions of n-butyllithium in hexane. Herren and Walsoe de Reca 2 found x ϭ 0.053 in Li x InSb was the limiting composition under these conditions.As suggested by the authors of Ref. 1, further work is required to determine the exact structural transformations that occur during the discharge and c...

Lithiation of InSb andCu2Sb: A theoretical investigation

“…In atoms are extruded beyond this concentration of Li, leading to very little further volume expansion. These results show best agreement with the experimental conclusions of Tostmann et al 12 The maximum number of intercalated Li atoms before In extrusion as reported by Hewitt et al 10 is almost half the value obtained in the present work. According to the energetics, the compound Li 2 InSb is unstable, but if formed leads to an enormous volume expansion of 15.4%.…”

Alloy-Based Anode Materials

“…This means that Li 2 Sb is not re-formed during delithiation. The second lithiation shows two plateaus again, but the first one is now observed at *0.89 V and probably still corresponds to the equilibrium between Sb and Li 2 Sb [116], which has been seen before using in situ XRD [117].…”

Nanostructured Antimony/carbon Composite Fibers as Anode Material for Lithium-ion Battery

“…8 shows the cyclic voltammetry (CV) curves of product Sb5 in the initial three cycles. The reversible electrochemical reaction formula in lithium ion battery can be described as the lithium alloying/de-alloying in antimony [54][55][56]:…”